The invention is directed to a multi-dimensional (k-dimensional) digital filter and more particularly to such a filter which is made up of adders, multipliers and shift elements.
Filters of this species are known, for example, from the periodical IEEE Transactions on Circuits and Systems, Vol. Cas-31, No. 1, January 1984, pages 31 through 48. Digital circuits and systems are described, including multi-dimensional digital filters. Wave digital filters have been described as specific digital filters in, for example, the periodical AEU, Vol. 25, 1971, pages 79 through 89 and also in German Pat. No. 20 27 303, these representing a specific species of digital filters. Classes of filters can be directly simulated in these wave digital filters. Finally, German Pat. No. 26 39 568 discloses multi-dimensional wave digital filters. A specific species of such wave digital filters has been described in K. Meerkotter, "Antimetric wave digital filters derived from complex reference circuits", Proc. Eur. Conf. Circuit Theory and Design, Stuttgart, W. Germany, September 1983, pages 217 through 220. Antimetrical wave digital filters that are derived from complex reference circuits are discussed therein (author: Klaus Meerkotter).
The use of such filters depends substantially on the respectively available technology. However, advances that have been achieved in VLSI technology bring real-time multi-dimensional filters into the realm of practical realization in comparison to earlier, complicated and comparatively slow computers. A bibliography of publications is attached hereto as an Appendix.